Question

an object of mass 5kg falls from rest through a vertical distance of 20m and acquires a velocity of 10m/s thé work done by the push of air on the object is

Answer 1

From work energy theorem work done by weight + work done by air =ΔKE

Wair=ΔKE−W(weight)

=12mv2−mgh

=12×5×(10)2−5×10×20

=−750J